from __future__ import division
import math
#tan(alpha)=s/c;
#helical antenna Gdmax=15NSC^2/lamda^3
c=1;
n=20;
lamda=1;
s=math.tan(0.2093)*1; #12*math.pi/180 radians
Gdmax=(15*n*s*(c)**2)/(lamda)**3;
print("The directive gain is %.3f"%Gdmax)
from __future__ import division
import math
#helical antenna
#part a
c=3*10**8;
f=3*10**9;
lamda=c/f;
print("The wavelength is %g m"%lamda);
#part b
n=20;
s=0.03;
c=0.1;
Gdmax=(15*20*0.3*(0.1)**2)/(0.1)**3;
print("The directive gain is %g"%Gdmax);
#part c
HPBW=math.sqrt((0.1)**3/(20*0.03))*520;
print("The half power beamwidth is %g degree"%HPBW)
from __future__ import division
import math
#loop antenna
r=10;
lamda=100;
A=(math.pi)*r**2;
Rr=31200*(A/lamda**2)**2;
print("The radiation resistance is %g ohm"%Rr);
from __future__ import division
import math
#loop antenna
l=1;
b=1;
A=l*b;
lamda=100;
Rrad=31200*(A/lamda**2);
print("The radiation resistance is %g ohm"%Rrad);